<?php

/**
 * 
 */
class B
{
	public static function xbs()
	{
		# code...
	}
}

class A  extends B
{
	public static $num=0;

	public function add()
	{
		// self::$num++;
		// echo self::$num;
		// parent::xbs();
	}

	public static function run()
	{
		echo "我是静态方法";
	}
	
}

echo A::$num;

A::run();